College Physics:
11th Edition
ISBN: 9781305965515
Author: SERWAY, Raymond A.
Publisher: Brooks/Cole Pub Co
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Textbook Question
Chapter 14, Problem 71AP
Assume a 150 W loudspeaker broadcasts sound equally in all directions and produces sound with a level of 103 dB at a distance of 1.60 m from its center. (a) Find its sound power output. If a salesperson claims the speaker is rated at 150. W, he is referring to the maximum electrical power input to the speaker. (b) Find the efficiency of the speaker, that is, the fraction of input power that is converted into useful output power.
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Chapter 14 Solutions
College Physics:
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Ch. 14 - Explain how the distance to a lightning bolt (Fig....Ch. 14 - Two cars are on the same straight road. Car A...Ch. 14 - Why does a vibrating guitar string sound louder...Ch. 14 - You are driving toward the base of a cliff and you...Ch. 14 - Prob. 8CQCh. 14 - Prob. 9CQCh. 14 - Prob. 10CQCh. 14 - An airplane mechanic notices that the sound from a...Ch. 14 - Suppose you hear a clap of thunder 16.2 s after...Ch. 14 - Earthquakes at fault lines in Earths crust create...Ch. 14 - On a hot summer day, the temperature of air in...Ch. 14 - A dolphin located in seawater at a temperature of...Ch. 14 - A group of hikers hears an echo 3.00 s after...Ch. 14 - The range of human hearing extends from...Ch. 14 - Prob. 7PCh. 14 - A stone is dropped from rest into a well. The...Ch. 14 - A hammer strikes one end of a thick steel rail of...Ch. 14 - A person standing 1.00 m from a portable speaker...Ch. 14 - The mating call of a male cicada is among the...Ch. 14 - The intensity level produced by a jet airplane at...Ch. 14 - One of the loudest sounds in recent history was...Ch. 14 - A sound wave from a siren has an intensity of...Ch. 14 - A person wears a hearing aid that uniformly...Ch. 14 - The area of a typical eardrum is about 5.0 105...Ch. 14 - The toadfish makes use of resonance in a closed...Ch. 14 - A trumpet creates a sound intensity level of 1.15 ...Ch. 14 - There is evidence that elephants communicate via...Ch. 14 - A family ice show is held at an enclosed arena....Ch. 14 - A train sounds its horn as it approaches an...Ch. 14 - An outside loudspeaker (considered a small source)...Ch. 14 - Show that the difference in decibel levels 1 and 2...Ch. 14 - A skyrocket explodes 100 m above the ground (Fig....Ch. 14 - The Doppler Effect A baseball hits a car, breaking...Ch. 14 - A train is moving past a crossing where cars are...Ch. 14 - A commuter train passes a passenger platform at a...Ch. 14 - An airplane traveling at half the speed of sound...Ch. 14 - Two trains on separate tracks move toward each...Ch. 14 - At rest, a cars horn sounds the note A (440 Hz)....Ch. 14 - An alert physics student stands beside the tracks...Ch. 14 - A bat flying at 5.00 m/s is chasing an insect...Ch. 14 - A tuning fork vibrating at 512 Hz falls from rest...Ch. 14 - Expectant parents are thrilled to hear their...Ch. 14 - A supersonic jet traveling at Mach 3.00 at an...Ch. 14 - A yellow submarine traveling horizontally at 11.0...Ch. 14 - Two cars are stuck in a traffic jam and each...Ch. 14 - The acoustical system shown in Figure P14.38 is...Ch. 14 - Prob. 39PCh. 14 - Prob. 40PCh. 14 - A pair of speakers separated by a distance d =...Ch. 14 - Prob. 42PCh. 14 - A stretched string fixed at each end has a mass of...Ch. 14 - Prob. 44PCh. 14 - A stretched string of length L is observed to...Ch. 14 - A distance of 5.00 cm is measured between two...Ch. 14 - A steel wire with mass 25.0 g and length 1.35 m is...Ch. 14 - Prob. 48PCh. 14 - A 12.0-kg object hangs in equilibrium from a...Ch. 14 - In the arrangement shown in Figure P14.50, an...Ch. 14 - Prob. 51PCh. 14 - Standing-ware vibrations are set up in a crystal...Ch. 14 - A cars 30.0-kg front tire is suspended by a spring...Ch. 14 - Prob. 54PCh. 14 - Prob. 55PCh. 14 - The overall length of a piccolo is 32.0 cm. The...Ch. 14 - The human ear canal is about 2.8 cm long. If it is...Ch. 14 - A tunnel under a river is 2.00 km long. (a) At...Ch. 14 - A pipe open at both ends has a fundamental...Ch. 14 - The adjacent natural frequencies of an organ pipe...Ch. 14 - A guitarist sounds a tuner at 196 Hz while his...Ch. 14 - Two nearby trumpets are sounded together and a...Ch. 14 - Prob. 63PCh. 14 - The G string on a violin has a fundamental...Ch. 14 - Two train whistles have identical frequencies of...Ch. 14 - Two pipes of equal length are each open at one...Ch. 14 - A student holds a tuning dork oscillating at 256...Ch. 14 - Prob. 68PCh. 14 - Some studies suggest that the upper frequency...Ch. 14 - A typical sound level for a buzzing mosquito is 40...Ch. 14 - Assume a 150 W loudspeaker broadcasts sound...Ch. 14 - Two small loudspeakers emit sound waves of...Ch. 14 - An interstate highway has been built through a...Ch. 14 - Prob. 74APCh. 14 - Prob. 75APCh. 14 - Prob. 76APCh. 14 - On a workday, the average decibel level of a busy...Ch. 14 - Prob. 78APCh. 14 - A block with a speaker bolted to it is connected...Ch. 14 - A student stands several meters in front of a...Ch. 14 - Prob. 81APCh. 14 - A 0.500-m-long brass pipe open at both ends has a...
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